"StressSmart" Repeated exposures to psychosocial stress are associated with several human diseases (e.g., cancer, drug addiction, heart disease, depression) of tremendous public health burden. However, our progress is limited by the lack of a portable device that can enable rapid, reliable, non-invasive and continuous measurement of personal exposure to psychosocial stress in real-time, as experienced by individuals in their natural environments. In this interdisciplinary project, we propose to develop a new test called InstaCortisol(tm) that can be used to reliably, selectively and rapidly quantify personal exposures to stress by measuring Cortisol levels of subjects in their natural environments. Cortisol is the primary steroid produced and secreted by the adrenal cortex and is used as a reliable indicator of stress. This rapid test is based on immunoelectrochemical method where the reaction signal is measured by using cyclic voltammetry, when Cortisol sandwiches between the capture and the detector antibody, which is attached to Alkaline Phosphatase enzyme. There are four specific aims of this project. First is Sensor Fabrication: We will fabricate multiple Cortisol sensors in first two months. Second is Sensor Evaluation: we will test the sensors for sensitivity, specificity, enzyme/antibody stability, detection limit, linearity, accuracy, dynamic range, repeatability, precision, accuracy, interference, cross-reactivity, drift, and sensor calibration. We anticipate changing and/or optimizing fabrication methods to achieve benchmarks in each of these categories. Third is sensor performance: Establish sensor performance against commercially available Cortisol sensors. We aim to meet or exceed, given the need for continuous performance benchmarks of readily available Cortisol sensors. Fourth would be to Design integration feasibility experiments: A virtual evaluation of Cortisol sensor chip and its integration into a compact easy to use design. Relevance: The InstaCortisol(tm) test (being developed during Phase I), which will be part of StressSmart(tm) device during Phase II, will enable researchers to quantify personal exposure to psychosocial stress, as experienced by individuals in real-life situations. Such a capability will advance our understanding of how exposures to psychosocial stress interact with genetic factors in the etiology of prevalent human diseases of tremendous public health burden. PUBLIC HEALTH RELEVANCE: We are proposing to make a rapid test for detecting Cortisol, called "InstaCortisol", which will make real-time and continuous measurements of personal exposure to psychosocial stress quantitatively, selectively, objectively, reliably, and securely by detecting Cortisol in interstitial fluid (ISF). ISF will be harvested using our proprietary minimally invasive device called "LightAccess". The proposed product involves the integration of several cutting edge technologies. The product would require virtually no action on the part of the subject or patient thereby greatly reducing error associated with improper use. These innovations would provide a significantly improved method for assessing a molecule that plays an important role in many biological processes and disease states.